To the possibility of using a linear scanner to create means of technical control of geometric parameters of the longitudinal section of the rolling surface of the railcar wheel

The subject of the study is the theoretical and practical aspects of the application of optical technologies for non-contact measurements of geometric parameters of a wagon wheelset during operation and repair. The purpose of the study is to develop methods and technologies for monitoring geometric parameters of car parts using an optical linear scanner, as well as a method for processing the results of field tests of the results of the application of optical control technologies. The article analyzes the problems of application of standardized methods of technical condition monitoring using manual measuring and control tools in the context of the adopted technology of maintenance and operation of freight cars. As a result of the study, a review of the state of the issue of the use of optical control techniques on the railway was carried out, the strengths and weaknesses of various options for the implementation of measurement techniques were identified and a methodology and a computer program for automating the creation of a digital standard of the object under study (the profile of the longitudinal section of the rolling surface of the wheelset) were developed. Using a digital two-dimensional image of the shadow pattern of the wheel profile, the coordinates of the points of the contour line of the section of the volumetric wheel in the area of the rolling surface are calculated. To determine the coordinates of the envelope of the section, a step function is used, as close as possible to the chiaroscuro image of the wheel contour. After image processing, the result is output by the program in the form of a table with the calculated coordinates of the profile section and visualized using the wheel profile synthesized by coordinates in the program window. The accuracy of the technique used depends on the resolution of the image obtained by the linear scanner. The methodology and program can be used in the future for field tests of the designed equipment for dimensional control of car parts.